In general, an antenna for wireless communication includes a feeding unit and a ground unit. The antenna further includes an antenna radiator connected to a RF circuit within a terminal device through the feeding unit and the ground unit, and a base supporting the antenna radiator.
The antenna radiator is formed of an electrically conductive material and has a pre-determined electrical length. Accordingly, the antenna radiator resonates at a target frequency to radiate and/or receive electromagnetic wave, and thus serves as a radiator. The antenna radiator may have a variety of shapes, such as a meander type, a helical type, a rectangular type, and a circular type, depending on its location and available space. The base is formed to support the antenna radiator and is also made of a dielectric material so that an effective wavelength of electromagnetic wave is reduced to reduce the electrical length of the antenna radiator.
Meanwhile, in recent years, as communication terminal devices are miniaturized and have light-weight, a built-in type antenna has been adopted increasingly. FIG. 1 is dismantled perspective view showing the conventional built-in type antenna. The conventional built-in type antenna includes a radiator unit 100 including a substrate 110 and a conductive antenna radiator 120 formed on the substrate, a base unit 200 supporting the radiator unit 100, and a terminal unit 300 that couples the antenna radiator 120 and a RF circuit (not shown). The terminal unit 300 is secured to the base unit 200 through a terminal hole 220. The radiator unit 100 is secured to the base unit 200 by a connection projection 230. If the terminal unit 300 is coupled to the base unit 200 and the radiator unit 100 is coupled to the base unit 200 as described above, a connection unit 130 of the antenna radiator 120 and the terminal unit 300 are electrically connected and the terminal unit 300 is coupled to the RF circuit, so that the antenna can operate.
In the conventional built-in type antenna constructed above, a conductor is generally deposited on the substrate 110 in order to form the antenna radiator 120. However, it is inconvenient and expensive to form the radiator 120 using the deposition process.
To solve the problem, a method of forming the antenna radiator 120 by printing electrically conductive ink on the substrate 10 has been proposed. The electrically conductive ink has conductivity since it contains micro-conductive particles such as silver (Ag). The electrically conductive ink can be printed on the substrate 110 and may serve as a radiator accordingly. The antenna radiator 120 can be formed by printing the electrically conductive ink on the substrate 110 in a predetermined shape through a method such as silkscreen printing. If the antenna radiator 120 is formed of the electrically conductive ink, the printing process is very simple, the productivity is very high, and various shapes of radiators can be formed.
If the antenna radiator is formed of the electrically conductive ink, however, there is a problem in that the gain of the antenna is low. Furthermore, since the electrically conductive ink is very expensive, the production cost of the antenna rises.
Therefore, there is a need for an antenna using electrically conductive ink and manufacturing method thereof, in which a manufacturing process of an antenna can be simplified, degree of freedom of design can be increased, a good gain can be obtained, and the production cost is low.